New subspecies of Caprimulgus sericocaudatus from the Amazon River Basin

[Bull. B.O.C. 1977: 95(1)]

18

Gyldenstolpe, N. 1924. Zoological results of the Swedish expedition to central Africa 1921.

Vertebrata. I. Birds. Kungl. Svenska Vetenskapsakad. Handl. (3), vol. 1, No. 3.

Jackson, Sir F. 1938. The birds of Kenya Colony and the Uganda Protectorate. Vol. 3. London:
Gurney and Jackson.

Neumann, O. 1908. [Estrilda atricapillagraueri, subsp. n.]. Bull. Brit. Orn. Cl. 21: 55.
Prigogine, A. In press. Les populations de Estrilda atricapilla (Verreaux) de l’Afrique
centrale et description d’une nouvelle race. Rev. Zool. ajr.

Reichenow, A. 1902. Neue afrikanische Arten. Orn. Monatsber. 10: 184-185.

— 1904/5. Die Vogel Ajrikas. Vol. 3. Neudamm: Neumann.

— 1912. Die Vo gel fauna des Mittelafrikanischen Seengebietes. Wiss. Ergebn. Deutsch.
Zentral-Afrika-Exped. 1907-1908. Vol. 3. Leipzig.

Sclater, W. L. 1930. Systerna avium Aethiopicarum. Part 2. London.

White, C. M. N. 1963. A revised check list of African flycatchers , etc. Lusaka: Govt. Printer.

New Subspecies of Caprimulgus sericocaudatus
from the Amazon River Basin

by Robert W. Dickerman

Received iyth November 1974

The Silky-tailed Nightjar Caprimulgus sericocaudatus is an exceedingly rare
species in North American ornithological collections. It is represented by
only six specimens from Misiones Province of Argentina; two from south¬
eastern Brazil (Sao Paulo and Curitiba); and the two specimens, on which the
species was described, from the Rivioli (Massena) Collection, labeled only
South America. De Schauensee (1970) also included Paraguay (Capitan Meza,
alto Parana) in the range of the species, but I have not been able to locate
(nor could he provide me with) the reference to this locality. The population
of the Amazon basin is represented by a specimen from Santarem, Brazil and
one from Yarinacocha in Amazonian Peru.

Recently Dr. Hannalore E. Hinsch made a collection of birds at the Insti-
tuto Veterinario de Investigaciones Tropicales y de Alturas 59 km east of
Pucallpa, Loreto, Peru, while carrying out a survey for arthropod-borne
viruses. The birds were shipped frozen to New York where they were
prepared and identified by the author to provide voucher specimens for
study. Included was a single specimen of this species.

Upon comparison of this individual with the three specimens available in
the American Museum of Natural History, differences were noted and thus
the above enumerated material was assembled (except for the two specimens
of the type series).

The characters noted proved consistent, and comparisons of representative
birds with the type series in the Academy of Natural Sciences of Philadelphia
immediately indicated that the name sericocaudatus was not based upon birds
from the Amazon basin, and that population awaited description. However,
first it was necessary to restrict the type locality of the nominate form. Stone
(1899) compiled a list of the types in the Academy and cited the bird upon
which the description was based (No. 21,905) as the type and it bears a type
label although it was not so designated in the original description. Cory
( 1 919) gave the range as “southeastern Brazil, Bahia, southwards”. Mr.
R. M. de Schaeunsee (in conversation) informed me that most early collec¬
tions from southeastern Brazil were exported from Bahia or Rio de Janiero.
The species was not recorded from the state of Bahia by Olivero M de O.
Pinto (1935). As first revisor of the species, I suggest restricting the type
locality of Caprimulgus (Antrostomus) sericocaudatus (Cassin) 1849 to t ^ ie
vicinity of Rio de Janiero, Brazil, that being a probably source of the type

19

\BulL B.O.C. 197j: 95 ( 1 )]

material closest to the range of the species as indicated by presently available
specimens.

It should be noted that Cory, and de Schauensee ( loc. cit) were in error
in citing the publication date for the species as 1848. The original description
bears the date 30 October 1849 an d was correctly cited by Stone (Joe. cit.) and
Peters (1940).

The population of the Amazon River Basin may now be described as:

Caprimulgus sericocandatus mengeli subsp. nov.

Diagnosis: Smaller (see Table) and darker, more sooty, than the nominate
form.

TABLE

Measurements of Capri mulgus sericocaudatus

wing tail

males

females

males

females

sericocaudatus

177-182

167-184

144-148

136-147

179-4

175-8

146-4

141-4

(n=5)

( n= 5 )

(n=5)

(n=5)

mengeli

157 & 163

156

124 & 127

I l6*

* Tail apparently retained from first basic plumage.

Type: American Museum of Natural History, no. 811079, adult male,
collected by Hannalore E. Hinsch, on 15th November 1972 at Instituto
Veterinario de Investigaciones Tropicales y de Alturas, 59 km east of
Pucallpa, Loreto Department, Peru. Original field number HEH-A-506.

Range: Amazon River basin.

Material: Besides the type, a $ from Yarinacocha, Peru, and a $ from
Santarem, Brazil.

Name: With great satisfaction I name this form for Dr. Robert M. Mengel,
student of Caprimulgids and friend.

Notes: De Schauensee (1970) has described the female plumage of the
species. The “young” bird mentioned in the original description is in reality
another adult male with a slight difference in wing formula. The only female
of mengeli is the Santerem specimen, which appears to be an immature. Its
rectrices are narrower and more rounded and are only diffusely tipped with
buff as compared to those of the other available apparently adult females.

ACKNOWLEDGEMENTS

I am grateful to the curators of the Los Angeles County Museum, Carnegie
Museum, Field Museum of Natural History and the Academy of Natural
Sciences of Philadelphia for loaning material or for allowing me to examine
specimens in their care.

References:

Cassin, J. 1849. Descriptions of new species of the family caprimulgidae, specimens of
which are in the collections of the Academy of Natural Sciences of Philadelphia. Proc.
Acad. Nat. Sci. Phila. 4: 236-239.

Cory, C. B. 1919. Catalogue of birds of the Americas , Part II, No. 2. Field Mus. Nat. Hist. Pub.
197, Zool. Series XIII.

De Schauensee, R. M. 1970. A guide to the birds of South America. Edinburgh: Oliver & Boyd.
Pinto, Oliver M. de O. 1935. Aves. da Bahia. Rev. Mus. Paul. (XIX), 19: 1-326.

Peters, James L. 1940. Check-list of birds of the world 4: 1-291. Cambridge, Mass.: Harvard
Univ. Press.

Stone, W. 1899. A study of the type specimens of birds in the collection of the Academy of
Natural Sciences of Philadelphia, with a brief history of the collection. Proc. Acad.
Nat. Sci. Phila. 51:5 91.